Lab Physical and Chemical Changes PDF

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Lab Activity: Physical and Chemical Changes Content Objective: Students will differentiate between chemical and physical changes by conducting a series of experiments Materials: Spaghetti Vinegar Chocolate Water Gel food colors

Lemon juice Eggs Corn flour Ice Trays

Purpose: Upon completion, the learner will be able to differentiate between physical and chemical changes. Physical changes occur when objects undergo a change that does not change their chemical nature. A physical change involves a change in physical properties. Physical properties can be observed without changing the type of matter. Examples of physical properties include: texture, shape, size, color, odor, volume, mass, weight and density. To identify a chemical change look for observable signs such as color change, bubbling and fizzing, light production, smoke, and presence of heat.

Physical and Chemical Change Experiments Directions: Record all observations on the investigation table. Talk about the “Discussion Question(s)” with your group. Talk about the “Discussion Question(s)” with your group. Experiment A: Chocolate 1. Observe and describe the chocolate at your table. 2. Break the chocolate into small pieces. a. Is this a physical or chemical change? 3. Add water into a pan and put the pan over the stove. Drop the chocolate pieces into the pan. 4. Observe what happens. a. Is this a physical or chemical change? Experiment B: Ice 1. 2. 3. 4.

Fill the ice tray with water. Put that ice tray in the freezer. Set the cup and ice cube in the freezer until you are finished with the other experiments. Observe what happens. a. Is this a physical or chemical change?

Experiment C: Spaghetti 1. 2. 3. 4.

Fill a pan with water and let the water boil. Add spaghetti in the boiling water and wait until they change their consistency. Strain the boiled spaghetti to remove water. Observe and record the changes. a. Is this a physical or chemical change?

Experiment D: Egg and vinegar 1. Break an egg. 2. Separate the egg white and egg yolk from the egg. Put the egg whites in one bowl and egg yolks in the other. 3. Add 5 ml of vinegar in the egg white. 4. Observe and record the change. a. Is this a physical or chemical change? Experiment E: Egg and lemon juice 1. Break an egg. 2. Separate the egg white and egg yolk from the egg. Put the egg white in one bowl and egg yolk in the other. 3. Add 5 ml of lemon juice in the egg white. 4. Observe and record the change. a. Is this a physical or chemical change? Experiment F: Eggs 1. Place a pan on the stove and add the mixture of egg and vinegar on it. 2. Let the egg cook. 3. Observe and record the change. a. Is this a physical or chemical change? 4. Wash the pan and reuse it for cooking the mixture of egg and lemon juice. 5. Let the egg cook. 6. Observe and record the change. a. Is this a physical or chemical change? 7. Taste the eggs. Discussion Question – Taste the eggs and discuss about the difference in taste that you feel. Why do you think there is a difference in the taste? Experiment G: Corn flour and water Take ½ cup of water and add 1 drop of food color into it. Mix 1 cup of corn flour to 1/2 cup of colored water into a bowl. Mix the cornstarch and water until your oobleck is formed. If you find the mixture is a little too watery and not forming into a solid when you pull the oobleck out of your bowl then add more cornstarch. If you find the mixture is not dripping like a liquid, add a little more water. Just keep experimenting until you get the consistency of oobleck! 5. Observe and record the change. a. Is this a physical or chemical change? 1. 2. 3. 4.

Experiment A B C D E F G

Original Substance(s)

Description Before Change (Use at least 3 adjectives)

Description During Change

Chocolate

Ice

Spaghetti

Egg & Vinegar

Egg & Lemon Juice

Eggs

Corn flour & Flour

1. The breaking of chocolate was an example of: A. Chemical Change B. Physical Change C. Neither a Physical or Chemical Change D. Both a Physical and Chemical Change 2. If a substance changes color then what has occurred? A. Physical Change B. Chemical Change C. Either a Physical or Chemical Change D. Neither a Physical or Chemical Change

3. Which of the following is not an example of a physical change? A. New substance is formed B. Change in its state of matter

Description After Change (Use at least 3 adjectives)

Is it a physical or chemical change?

C. Change in volume D. Change in texture 4. When gases are released from a reaction what type of change has occurred? A. Physical B. Chemical C. Neither D. Both 5. Which of the following is an example of a chemical reaction? A. Ice melting B. Paper being torn C. Combining of vinegar and baking soda D. Crushing of the antacid...